Vitamin B6 derivatives as protective components in the oxidative treatment of hair

The use of compounds corresponding to formula (I):

• 3
• in which
• A and B independently of one another represent hydrogen, halogen, a C1-4 alkyl group, a C3-6 cycloalkyl group, a C1-4 monohydroxyalkyl group, a C2-4 oligohydroxyalkyl group, a C1-4 aminoalkyl group, a group —OR or a group —NR1R2, where R1 and R2 independently of one another represent hydrogen, a C1-4 alkyl group or a C1-4 monohydroxyalkyl group or R1 and R2 together with the nitrogen atom form a saturated ring,
• C represents a group —OR, —NR1R2, —OP(O)(OR3)2, a C1-4 monohydroxyalkyl group, a C2-4 oligohydroxyalkyl group or a C1-4 alkyl group,
• D represents a group —OR, a carboxy group, a C1-22 alkoxycarbonyl group, a formyl group, a group —CH2OR or a group —CH2—NR2,
• E represents a group —OR, —OP(O)(OR3)2, a C1-4 monohydroxyalkyl group or a C2-4 oligohydroxyalkyl group,
• R representing hydrogen, a C1-4 alkyl group, a C1-22 acyl group, a hydroxy-C2-22-acyl group, a C2-10 carboxyacyl group, a C3-10 oligocarboxyacyl group, an oligocarboxymonohydroxy-C3-10-acyl group, an oligocarboxyoligohydroxy-C3-10-acyl group, a C3-8 cycloalkyl group, a C1-4 monohydroxyalkyl group, a C2-4 oligohydroxyalkyl group, an aryl group which may contain a hydroxy, nitro or amino group, a heteroaromatic group or a group —CH2CH2NR1R2, where R1 and R2 are as defined above,
• R3 representing hydrogen or a C1-5 alkyl group,
• or one of the corresponding physiologically compatible salts, for reducing the damage to keratinous fibers, especially human hair, by oxidative processes.